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TR2/3/3A Who is running a Sleeved Thermostat in their TR3?

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Karl-

I used to run one, before the price went up. However, I was lucky in that I spotted when it failed - if the bellows leaks it fails shut, which means you overheat. Not a quality issue, but I won't buy one again - you can partially plug the bypass line and achieve similar results anyway for much less money.

Randy
 
I ran my original 160 degree unit until last fall (from 1966)when it failed. Mine failed open however. I found a used 180 sleeved unit but decided to go with a non sleeved one instead. I have not blocked my bypass hose and had no issues during a recent 1800 mile trip. I've not been caught in stop and go traffic however and it's not real hot in Ohio yet.
 
I run one, but I got it a couple of years ago when (I forget who) had it on sale for about $40. If you use a standard type thermostat, put a restriction in the by-pass hose. There's a copper plumbing cap that fits nicely in the hose. Drill a small hole in it, say about 1/4". That will allow some circulation, which I feel is necessary.
 
I guess I did not answer your original question. When I looked into this last year I could not find one for less than Moss sells them for.
 
I am using one that I grabbed in ebay at a reasonable cost: 12.71 euro including shipping to Spain....(Anyway, this was back in January 2008).
JesĂşs
 
martx-5 said:
...If you use a standard type thermostat, put a restriction in the by-pass hose. There's a copper plumbing cap that fits nicely in the hose. Drill a small hole in it, say about 1/4". That will allow some circulation, which I feel is necessary.
Click to expand...

That is what I use, copper cap is 3/4", hole is about 3/16.

bypasshose.JPG
 
Or just do without. I've tried several configurations, and blocking the bypass has never seemed to help with my overheating problems, nor improve anything when I wasn't having problems.

The main issue with a TR3A is air flow through the radiator, IMO. Or just a bad radiator, which has turned out to be my problem twice now (even after the radiator shop said it was fine).

If the bottom tank is just as hot as the top tank (or nearly so), then forcing more water through the radiator is not going to help.
 
I agree fully with Randall. I tried everything to solve my overheating problem, and nothing worked until I installed a new Wizard Aluminum Rad + a big Spal fan. What a difference, my gauge barely goes above 165 now.

Actually, installing the copper plug in the bypass hose caused me a big problem...I think too much pressure built up and the hose burst after only a couple of months.
 
What would we like to see as the temp drop from top to bottom tank? Is a fair test to make the reading at idle?
 
TRclassic3 said:
What would we like to see as the temp drop from top to bottom tank? Is a fair test to make the reading at idle?
Click to expand...
Well, it would tell you something about cooling performance at idle. But I don't think it will tell you anything about whether blocking the bypass is helping or not.

The problem is that when the system is working normally, the thermostat always limits the water flow through the radiator. The effect of the reduced water flow is that you will see a larger temperature difference from top to bottom; but that is exactly what is supposed to happen. So, blocking the bypass makes no difference to cooling until the thermostat is fully open (or at least nearly so) and the engine is already starting to get hotter than normal.

But at idle, there is very little heat being produced (compared to even cruise conditions, let alone full throttle). So the only way it can start to get hot at idle is if there is not enough airflow through the radiator (or something seriously wrong with the system).
 
I run a sleeved Smiths thermostat in both of my tr3 because I was doing everything I could think of to try and cool the engine down. A new copper re- cored radiator helped some, but I think you will find that the fan configuration is paramount for good cooling. My 58 runs cool with that configuration with a tropical fan. My 61 runs very cool with an original radiator that I had rodded out and one of those yellow plastic fans. In fact the 61 runs so cool I keep checking it with a thermometer because I figured the gauge was wrong, but it runs at about 170 even after a long idle. I am not sure if it is the yellow fan or that the OE radiator is helping it run cool; perhaps, the OE radiator has better tubs and fins on it.
 
I'm in the process of re-furbing my cooling system right now. I've never had cooling problems but, my water pump has started howling recently.

I've run a 100% stock system including radiator (cleaned 12 years ago), rad duct, cooling fan, TRF water pump and a cheap t-stat.

I'm considering upgrading to a 6 vane water pump but not completely decided yet. I have ordered a Stant SuperStat t-stat from Summit Racing ($11 with S&H). I've compared it to the old t-stat and it is very obvious, once open, it will flow considerably more coolant into the rad. I've also realized the PO installed the stock fan backwards. It still pulls air in the right direction (installed forwards or backwards, the blades will be angled correctly) but, the curve in the blades is facing the wrong way - probably reducing effectiveness some.

I've decided not to us a restriction in the by-pass hose. Just not comfortable about possibly creating hot spots in the head.

Regarding choice of fans, these only matter at idle or at traffic. If you're running hot at speed (say 35+ mph) you're issues are definitely not with the fan.

Last, in order to max cooling efficiency of the system, I run a mixture of 38% coolant, 5% Water Wetter and 57% water (103oz, 12oz and 154oz respectively). While coolant raises the boiling temp, the water is more efficient at thermally transferring the heat out of the engine. And I change it every other year. I also jack the front end of the car and be sure to burp ALL the air from the system.

Bob
 
RJS said:
Regarding choice of fans, these only matter at idle or at traffic. If you're running hot at speed (say 35+ mph) you're issues are definitely not with the fan.
Click to expand...
:iagree:

I converted to electric, because I was having trouble with the stock fan not being enough in long traffic jams and I didn't want the extra power drain of a more aggressive mechanical fan. The electric fan doesn't run at all unless I'm in fairly heavy traffic, or idling in the driveway, or stopped suddenly after a long high speed run on a hot day.
 
X3 on the use of Tropical Fans.

I never had any overheating but things would get a bit warm in Tucson traffic on 100° days so I added (manually switched) pusher electrics to help the stock set-up.

After I changed to tropical fans I realized I had no need of thsoe electrics -- at idle and low speeds the much greater air movement from the 6-bladed fan was plenty.

FWIW -- I use 25/75 coolant mix (no freezing temps here), tropical fan, stock pump, crank hole in the TR3A rad, bypass mostly blocked, air dam on the front, recovery bottle added to the TR4.

I often (about once a week this time of year) drive from the 100°+ desert up the mountain to 7000' in 16 miles with no heat issues (other than me that is).

Yours (anyone's) for the shipping cost -- used electric fan with mounting hardware suitable for the TR3/4 radiator. PM if interested.

fan.JPG


fan8.JPG
 
The way I see it is the electric fan assembly shields the cooling fins from performing to their maximum potential by blocking air flow. I used an electric fan for a while 30 years ago on my tr3, and they have probably improved since then, but mine would drain my battery on those dark rainy nights when I had everything else on, so I would sometimes turn the heater and radio off and run the headlights and fan. Now that I have the more improved fan, I can run everything without the prince of darkness sitting too close. Of course, there is always that struggle between darkness and light, but that might be a different post.
 
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